Why global water shortages pose threat of terror and war

On 17 January, scientists downloaded fresh data from a pair of Nasa satellites and distributed the findings among the small group of researchers who track the world's water reserves. At the University of California, Irvine, hydrologist James Famiglietti looked over the data from the gravity-sensing Grace satellites with a rising sense of dread.

The data, released last week, showed California on the verge of an epic drought, with its backup systems of groundwater reserves so run down that the losses could be picked up by satellites orbiting 400km above the Earth's surface.

"It was definitely an 'oh my gosh moment'," Famiglietti said. "The groundwater is our strategic reserve. It's our backup, and so where do you go when the backup is gone?"

That same day, the state governor, Jerry Brown, declared a drought emergency and appealed to Californians to cut their water use by 20%. "Every day this drought goes on we are going to have to tighten the screws on what people are doing," he said.

Seventeen rural communities are in danger of running out of water within 60 days and that number is expected to rise, after the main municipal water distribution system announced it did not have enough supplies and would have to turn off the taps to local agencies.

There are other shock moments ahead – and not just for California – in a world where water is increasingly in short supply because of growing demands from agriculture, an expanding population, energy production and climate change.

Already a billion people, or one in seven people on the planet, lack access to safe drinking water. Britain, of course, is currently at the other extreme. Great swaths of the country are drowning in misery, after a series of Atlantic storms off the south-western coast.

But that too is part of the picture that has been coming into sharper focus over 12 years of the Grace satellite record. Countries at northern latitudes and in the tropics are getting wetter. But those countries at mid-latitude are running increasingly low on water.

"What we see is very much a picture of the wet areas of the Earth getting wetter," Famiglietti said. "Those would be the high latitudes like the Arctic and the lower latitudes like the tropics. The middle latitudes in between, those are already the arid and semi-arid parts of the world and they are getting drier."

And that is why, according to The Nation, the United Arab Emirates are interested in a solar-powered French device that converts humidity into drinking water.

On 17 January, scientists downloaded fresh data from a pair of Nasa satellites and distributed the findings among the small group of researchers who track the world's water reserves. At the University of California, Irvine, hydrologist James Famiglietti looked over the data from the gravity-sensing Grace satellites with a rising sense of dread.

The data, released last week, showed California on the verge of an epic drought, with its backup systems of groundwater reserves so run down that the losses could be picked up by satellites orbiting 400km above the Earth's surface.

"It was definitely an 'oh my gosh moment'," Famiglietti said. "The groundwater is our strategic reserve. It's our backup, and so where do you go when the backup is gone?"

That same day, the state governor, Jerry Brown, declared a drought emergency and appealed to Californians to cut their water use by 20%. "Every day this drought goes on we are going to have to tighten the screws on what people are doing," he said.

Seventeen rural communities are in danger of running out of water within 60 days and that number is expected to rise, after the main municipal water distribution system announced it did not have enough supplies and would have to turn off the taps to local agencies.

There are other shock moments ahead – and not just for California – in a world where water is increasingly in short supply because of growing demands from agriculture, an expanding population, energy production and climate change.

Already a billion people, or one in seven people on the planet, lack access to safe drinking water. Britain, of course, is currently at the other extreme. Great swaths of the country are drowning in misery, after a series of Atlantic storms off the south-western coast.

But that too is part of the picture that has been coming into sharper focus over 12 years of the Grace satellite record. Countries at northern latitudes and in the tropics are getting wetter. But those countries at mid-latitude are running increasingly low on water.

"What we see is very much a picture of the wet areas of the Earth getting wetter," Famiglietti said. "Those would be the high latitudes like the Arctic and the lower latitudes like the tropics. The middle latitudes in between, those are already the arid and semi-arid parts of the world and they are getting drier."

And that is why, according to The Nation, the United Arab Emirates are interested in a solar-powered French device that converts humidity into drinking water.